54x^3 +250 factor

Answer 1

sum of two cubes:

(a^3+b^3)=(a+b)(a^2-ab+b^2)

cubrt (54x^3)=3xcubrt2
cubrt (250)=5cubrt2
Let k=cubrt2

(3xk+5k)(9x^2k^2-15xk^2+25*k^2)

k^3 (3x+5)(9x^2-15x+25) and k^3=2

Answer 2

I'd have factored out the 2 first, leaving

2(27x^3 + 125)
= 2((3x)^3 + 5^3))
= 2(3x+5)(9x^2 - 15x + 25)